Communication devices, such as handheld two-way radios, cellular telephones and the like, often include a keypad as part of a user interface. While communication devices become smaller, the keypad design remains driven by human factors and usability. When designing communication devices which are expected to operate under adverse environments, sealing the keypad is also taken into consideration. Space constraints in portable communication devices make the implementation of a sealed keypad extremely challenging. Keypad assemblies incorporating backlighting further exacerbate the sealing challenge as the need for uniform illumination distribution must also be taken into account.
It is particularly important that handheld communication devices, such as battery operated two-way radios utilized by public safety personnel, operate under a variety of oftentimes adverse conditions within the public safety arena. As such, these types of devices demand higher performance factors including sealing, power consumption, backlighting, robustness and physical size which must be balanced with ease of manufacturing and cost. Many past keypad assemblies have been bulky and non-energy efficient.
Accordingly, it would be desirable to have a robust, water-sealed keypad assembly with improved backlighting which addresses the design and performance concerns for handheld communication devices.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.